Chapter 2: Find out if you're wrong, before you build, lesson 1 of 7

Find the beliefs behind an idea

Every idea rests on beliefs nobody has checked. Learn to find them and play the 2-4-6 game. Then ask the question that saves you: how would I know I'm wrong?

By 5 min read, 15 min of exercises

Warm-up

One thing from chapter 1 first. Office managers say these things about lunch at work. Is each one a frustration, a motivation or an aspiration?

  1. I have to chase people who reply late.

    Right, it's frustration. It goes wrong today, and it costs them time.

    Not quite. It's frustration. It goes wrong today, and it costs them time.

  2. I want today's order in by eleven.

    Right, it's motivation. It gets them through today's task. Then it's done.

    Not quite. It's motivation. It gets them through today's task. Then it's done.

  3. I want my team to eat together.

    Right, it's aspiration. It's the kind of team they want to have. That keeps them doing it.

    Not quite. It's aspiration. It's the kind of team they want to have. That keeps them doing it.

In lesson 1.4, you made a bet: what is the fastest way to find out you’re wrong? This chapter answers it, with one story.

Imagine you’ve just joined Tiffin as its designer. Tiffin is a made-up company that delivers lunch to offices. You’ll stay with the same team all through this chapter.

On your first morning, Peter, the head of sales, sends this email to the product team. You’re on that team, so it’s in your inbox too.

From
Peter Hale, Head of Sales
To
Product team (you're on it, as the designer)
Subject
Group ordering this quarter?

Hi team,

Customers are asking for group ordering. Can we ship it this quarter?

Three big offices asked me about it this month, and we get tickets about groups all the time. LunchRun will do it before us if we wait. Everyone orders lunch as a team, so this could double our office orders.

The idea is simple: one person starts an order, shares a link, and everyone adds their own food.

Let me know by Friday so I can tell the offices.

Peter

Tiffin and everyone at it are made up for this course.

Think first

Before anyone builds group ordering, what has to be true for it to work? Write two or three things.

You

Which of these is closest to your answer?

Shirish

That’s one belief: that people who ask for a feature will use it. Is that always true?

Think about who orders, and who pays. What else has to be true?

Shirish

That’s a belief about the team. It matters, but it comes second.

What has to be true about the people ordering lunch?

Shirish

Yes. The whole idea depends on that. Has anyone checked it?

What would you look at to find out?

Shirish

That’s where I’d start too. Peter names a feature, not a problem.

So what is the first thing you would want to find out?

You

What this means

Every idea sits on beliefs like these. Most of them were never checked. Peter’s email sits on at least four:

  • Offices order lunch as a team, most days.
  • Placing the order is the hard part.
  • People will open a link and add their own meal.
  • It will bring more orders than it costs to build.

None of these is checked yet. That’s normal. The danger is not having beliefs. It’s treating them as facts.

What Peter’s email takes for granted

At the team meeting, everyone likes the idea. It sounds obvious. So before anyone builds, pull apart what is known from what is only believed.

Practice

Some of these already happened: they are in Peter's email. Others are bets that group ordering needs. Which is which?

  1. Three big offices asked Peter about group ordering this month.

    Right, it's already true today. It already happened. Peter says so in his email. It stays true whether the idea works or not.

    Not quite. It's already true today. It already happened. Peter says so in his email. It stays true whether the idea works or not.

  2. People will open a link and add their own meal.

    Right, it's a belief the idea needs. Group ordering only works if this is true. Nobody has checked it.

    Not quite. It's a belief the idea needs. Group ordering only works if this is true. Nobody has checked it.

  3. Peter wants an answer by Friday.

    Right, it's already true today. It's a fact about this week. The idea doesn't depend on it.

    Not quite. It's already true today. It's a fact about this week. The idea doesn't depend on it.

  4. Placing the order is the part people find hard.

    Right, it's a belief the idea needs. It's a guess about where the pain is. If the pain is somewhere else, the feature misses.

    Not quite. It's a belief the idea needs. It's a guess about where the pain is. If the pain is somewhere else, the feature misses.

  5. Group ordering will bring more orders than it costs.

    Right, it's a belief the idea needs. It's a bet about the future. Only a test can check it.

    Not quite. It's a belief the idea needs. It's a bet about the future. Only a test can check it.

  6. Peter says Tiffin gets help requests about groups.

    Right, it's already true today. It's something Peter has already seen. What those requests really ask for is still a question.

    Not quite. It's already true today. It's something Peter has already seen. What those requests really ask for is still a question.

Did you notice the pull? It’s easy to list what is already true and stop there. The beliefs are the bets hiding inside the idea, and they’re what can sink it. I learned that the expensive way.

Shirishfrom my own work

Three things my team believed about our education app

We built an education app for schools. My team believed three things, and each one felt obvious:

  • Students want games in their lessons. They found them childish.
  • Teachers want more features. They wanted simpler tools.
  • Parents check progress every day. Most checked once a month, at best.

Each belief felt reasonable. Each one cost us weeks of work. And each could have been checked before we built anything.

A belief like these, one your design depends on that nobody has checked, has a name: an assumption. Every idea sits on a stack of them. Peter’s does too.

Could asking prove Peter wrong?

Peter has a plan to check his idea. He’ll ask five more offices, Would you like group ordering?

Think first

Could asking five offices ever prove Peter wrong?

You

Which of these is closest to your answer?

Shirish

In theory, yes. But how often do people say no to a free new feature, when you ask them?

What would you expect five offices to say?

Shirish

That’s my worry too. Five polite yeses would feel like proof, and they wouldn’t be.

So what could Peter look at, that might go against him?

Shirish

It does. But any would you like it? question invites a yes.

What could offices do, instead of say?

You

What this means

Hold that thought. There’s a game that shows what is going on here. It takes about three minutes.

A thought experiment: the 2-4-6 game

Thought experiment

The 2-4-6 game

Peter Wason, 1960, with Karl Popper's idea of testing

Game

The 2-4-6 game

I have a rule for three numbers. 2, 4, 6 follows my rule. Find the rule.

  • Try any three numbers. I'll tell you if they follow the rule.
  • Before each try, say if you think it will.
  • You get 6 tries. After the last one, you write the rule.

2, 4, 6 Follows the rule

Try three numbers Try 1 of 6
Do you think they follow the rule?

Show the rule

The rule is any three numbers that go up. Most people guess add 2, because they only try numbers they expect to fit. A test is only worth running if it could prove you wrong.

Based on Peter Wason's 1960 experiment.

Finish the game above first. Then the story goes on.

Back to Peter. Asking five offices Would you like it? is like trying 8, 10, 12. You expect a yes, you get a yes, and you learn nothing. Wason’s players did the same, and most of them named the wrong rule.

Looking only for proof that you’re right has a name: confirmation bias. Its cure is a belief that some result could prove wrong. That kind of belief is called falsifiable.

Think first

Peter believes office managers will send colleagues a link to add their own meal.

Which result would prove him wrong?

You

Pick the answer closest to yours.

Shirish

That’s a nice thing to hear. But could it ever go against Peter? People like most ideas when you ask.

What would they have to do for Peter to be wrong?

Shirish

Yes. That result would tell Peter his belief is wrong. And it’s something you can see, not something people say.

How many managers would that need to be, before you’d believe it?

Shirish

That could happen for lots of reasons: a new menu, a sale, the weather. So it can’t tell you much about the link.

What would show the link itself isn’t being used?

You

What this means

Before you test anything, write down the result that would prove you wrong. If no result could, it isn’t a test. It’s a wish.

That’s the answer to your bet from lesson 1.4. The fastest way to find out you’re wrong: write down what would prove you wrong, then test that first.

Words from this lesson

These words come back all through this chapter.

Assumption
A belief your design depends on that nobody has checked yet. In this lessonPeter believes people will open a link and add their own meal.
Confirmation bias
Looking only for proof you’re right, so nothing can show you’re wrong. In this lessonTrying only numbers like 8, 10, 12, which you expect to fit.
Falsifiable
A belief is falsifiable when some result could prove it wrong. In this lessonIf most managers still type every order, Peter's belief is wrong.

Back to your first answer

Your first answer

Your answer

Your answer will show here after you write one at the top of this page.

You've read the lesson. Would you change your answer?
Good. Which part of this lesson backs your answer?

Your bet: what does Peter’s line need, to become a test?

Your bet

Next morning, Mia, Tiffin’s research lead, stops by your desk. Peter’s line needs to become a test, she says. Can you write it by Friday?

Peter, head of sales, replies to the team: Group ordering will get us more orders.

What does his sentence need before you could test it? Make your bet, and say how sure you are.

Your guess
How sure are you?

You'll find the answer in Lesson 2.2: Turn a belief into a test.

Try this during the week: pick one feature you use. What would have to be true for it to work? And what result would prove its makers wrong?

Sources

  • Peter Wason’s 1960 study in the Quarterly Journal of Experimental Psychology. The 2-4-6 game comes from it.
  • Karl Popper, Conjectures and Refutations, 1963. The idea that a test is only worth running if it could prove you wrong.
  • The education app is from my own work. Tiffin, Peter and Mia are made up for this course.
Portrait of Shirish Shikhrakar

Written by

Shirish Shikhrakar

Shirish is a Google-certified UX designer and UX engineer based in Kathmandu, Nepal. He started as a software developer, moved into product design for Silicon Valley startups, and has taught UX foundations to hundreds of designers since 2019.

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